Pilot Core Abstract Our Pilot Core will identify talented investigators and provide them with mentoring, support, and incentives that will enable them to test interventions that are highly scalable and have the capacity to advance science in our areas of thematic focus. This renewal application targets four thematic areas of focus: physical activity (PA) promotion, novel interventions that will maintain or enhance mobility in individuals, harnessing technology to promote healthy aging, and sustaining behavior change. This Pilot Core describes two proposed Year 1 pilot projects that will be undertaken by our Roybal renewal Center as well as Year 2 and subsequent pilots that are consistent with and will enable us to achieve the overall mission described above. These pilots will advance scientific knowledge in the engagement of understudied populations in physical activity (PA) and the ability of PA interventions to simultaneously affect mobility and cognition. The proposed pilots also incorporate technology into their intervention designs to increase fidelity and scalability and embed mechanisms of behavior change that will promote long-term adherence to PA. The Year 1 Bronas pilot proposes to harness the interactive effects of behavior determination to interrupt and replace sedentary behavior with bouts of PA in older Latinos at high risk for ADRD using an Ecological Momentary Intervention that will be tested with Ecological Momentary Assessment methods. The Year 1 Bhatt pilot seeks to examine the feasibility and effectiveness of combined PA and cognitive training (CogXergaming) in frail older adults for improving locomotor-balance control, cognition, muscle quality, and cardiovascular fitness; all of which will lead to increased PA, community mobility, and improved health-related quality of life. Both Year 1 pilots will obtain imaging data on a subsample of participants using our new Multimodal ADRD Imaging and Connectomics Core. This Core will assist investigators with participant recruitment, use of a uniform dataset to examine ADRD outcomes, and assistance with imaging as appropriate, including the management, storage and analysis of imaging data. The cumulative effects of these pilots and others like them will be substantial advances in science and practice concerning the engagement of understudied minority populations of older adults in PA and improved understanding about the interconnections between PA, mobility and brain health. Collectively, these interventions are expected to contribute to enhanced quality of life and independent functioning among older adults locally, regionally, and nationally.